a mercifully unnecessary neologism

In the epic contest between "related videos" on YouTube and "related articles" on Wikipedia to be my most crippling time-suck, "related articles" recently took the lead as I learned all about the War of the Spanish Succession, in particular, how Charles II of Spain was physically disabled, intellectually stunted, and emotionally unstable, and how this probably had something to do with the fact that his grandmother was simultaneously his aunt and he was descended from someone called "Joanna the Mad" in a total of 14 different ways. All of this prompted MS and I to create a new, kinda gross word--grandbrother: n., the male offspring of a marriage between one's child and one's (hopefully step-)parent.